Myopenhab cloud doesn't work with Alexa

Hi, since a week now alexa and myopenhab have some issue. Ok I use openhab 2.1 ( I know it’s an old version but it works fine befor) and since a week, alexa don’t find any devices. I check my installation and it works since years perfect. I uninstalled the cloudconnector and enable all services again but it doesn’t work. Have somebody an Idea what happen? I contact Amazon support but they have no idea what’s going wrong.
Thx for help

Can you still control your existing devices?

Is your server showing online in your account?

Make sure to go over the troubleshooting guide.

I can reach my habpanel over the cloud connection and switch lights on/off. Just alexa can not find any devices. All devices are selected so that alexa can find the devices.

What do you mean? Did you delete your existing devices on the Alexa end? Did you make any changes since the last time it was working? If so, could you share details?

Yes, I had to delete all devices. One morning, it stopped working without changes on openhab.
With selection, I mean you must select the devices in openhab that alexa can see it.

how / where did you select it ?
select might be the wrong wording ? Your setup need to use the correct alexa meta-data labels so that alexa knows what kind of device is available.
e.g. see Amazon Alexa Smart Home Skill | openHAB ( link points to v2 description )

To add to what @Wolfgang_S highlighted, could you provide details on your existing configuration? Since you are still OH 2.1, I assume you are using tags?